diff --git a/ChangeLog b/ChangeLog
index 65fcd4ebd4..97bb304f1f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -804,5 +804,11 @@
 
 0.4.10 2009-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
 
+	* lib/: Added some basic regex-subset, pattern matching functions
+	* lib/: Greatly simplified mktime() and gmtime_r().  The Gregorian and
+	  Julian time calculations were interesting, but not necessary in the
+	  typical embeddd system.
+
+
 
 
diff --git a/Documentation/NuttX.html b/Documentation/NuttX.html
index 36eba419ba..627a5bd6c6 100644
--- a/Documentation/NuttX.html
+++ b/Documentation/NuttX.html
@@ -8,7 +8,7 @@
   <tr align="center" bgcolor="#e4e4e4">
     <td>
       <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
-      <p>Last Updated: June 26, 2009</p>
+      <p>Last Updated: July 11, 2009</p>
     </td>
   </tr>
 </table>
@@ -1477,6 +1477,11 @@ buildroot-0.1.7 2009-06-26 &lt;spudmonkey@racsa.co.cr&gt;
 <pre><ul>
 nuttx-0.4.10 2009-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
+	* lib/: Added some basic regex-subset, pattern matching functions
+	* lib/: Greatly simplified mktime() and gmtime_r().  The Gregorian and
+	  Julian time calculations were interesting, but not necessary in the
+	  typical embeddd system.
+
 nuttx-0.4.10 2009-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
 pascal-0.1.3 2009-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 2580cf0b03..9acd622cdd 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -12,7 +12,7 @@
       <h1><big><font color="#3c34ec">
         <i>NuttX RTOS Porting Guide</i>
       </font></big></h1>
-      <p>Last Updated: June 18, 2009</p>
+      <p>Last Updated: July 11, 2009</p>
     </td>
   </tr>
 </table>
@@ -2054,7 +2054,14 @@ extern void up_ledoff(int led);
     Used to initialize the internal time logic.
   </li>
   <li>
-    <code>CONFIG_JULIAN_TIME</code>: Enables Julian time conversions
+    <code>CONFIG_GREGORIAN_TIME</code>: Enables Gregorian time conversions.
+    You would only need this if you are concerned about accurate time conversions in
+    the recent past or in the distant future.
+  </li>
+  <li>
+    <code>CONFIG_JULIAN_TIME</code>: Enables Julian time conversions.
+    You would only need this if you are concerned about accurate time conversion in the distand past.
+    You must also define <code>CONFIG_GREGORIAN_TIME</code> in order to use Julian time.
   </li>
   <li>
     <code>CONFIG_DEV_CONSOLE</code>: Set if architecture-specific logic
diff --git a/configs/README.txt b/configs/README.txt
index 8559418700..04833669b0 100644
--- a/configs/README.txt
+++ b/configs/README.txt
@@ -194,7 +194,13 @@ defconfig -- This is a configuration file similar to the Linux
 		  instrumentation is selected.  Set to zero to disable.
 		CONFIG_START_YEAR, CONFIG_START_MONTH, CONFIG_START_DAY -
 		  Used to initialize the internal time logic.
-		CONFIG_JULIAN_TIME - Enables Julian time conversions
+		CONFIG_GREGORIAN_TIME - Enables Gregorian time conversions.
+		  You would only need this if you are concerned about accurate
+		  time conversions in the past or in the distant future.
+		CONFIG_JULIAN_TIME - Enables Julian time conversions. You
+		  would only need this if you are concerned about accurate
+		  time conversion in the distand past.  You must also define
+		  CONFIG_GREGORIAN_TIME in order to use Julian time.
 		CONFIG_DEV_CONSOLE - Set if architecture-specific logic
 		  provides /dev/console.  Enables stdout, stderr, stdin.
 		CONFIG_MUTEX_TYPES - Set to enable support for recursive and
diff --git a/include/nuttx/regex.h b/include/nuttx/regex.h
index b6fee93746..15f44a7478 100644
--- a/include/nuttx/regex.h
+++ b/include/nuttx/regex.h
@@ -49,11 +49,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Global Function Prototypes
- ****************************************************************************/
-
-/****************************************************************************
- * Global Function Prototypes
+ * Public Function Prototypes
  ****************************************************************************/
 
 #ifdef __cplusplus
diff --git a/include/nuttx/time.h b/include/nuttx/time.h
new file mode 100644
index 0000000000..1e5e50cb52
--- /dev/null
+++ b/include/nuttx/time.h
@@ -0,0 +1,114 @@
+/****************************************************************************
+ * include/nuttx/time.h
+ *
+ *   Copyright (C) 2009 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef __INCLUDE_NUTTX_TIME_H
+#define __INCLUDE_NUTTX_TIME_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+
+/****************************************************************************
+ * Pre-Processor Definitions
+ ****************************************************************************/
+
+/* If Gregorian time is not supported, then neither is Julian */
+
+#ifndef CONFIG_GREGORIAN_TIME
+#  undef CONFIG_JULIAN_TIME
+#else
+#  define JD_OF_EPOCH           2440588    /* Julian Date of noon, J1970 */
+
+#  ifdef CONFIG_JULIAN_TIME
+#    define GREG_DUTC           -141427    /* Default is October 15, 1582 */
+#    define GREG_YEAR            1582
+#    define GREG_MONTH           10
+#    define GREG_DAY             15
+#  endif /* CONFIG_JULIAN_TIME */
+#endif /* !CONFIG_GREGORIAN_TIME */
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifndef CONFIG_GREGORIAN_TIME
+extern uint16 g_daysbeforemonth[13];
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C" {
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Function:  clock_isleapyear
+ *
+ * Description:
+ *    Return true if the specified year is a leap year
+ *
+ ****************************************************************************/
+
+#ifndef CONFIG_GREGORIAN_TIME
+EXTERN int clock_isleapyear(int year);
+#endif
+
+/****************************************************************************
+ * Function:  clock_calendar2utc
+ *
+ * Description:
+ *    Calendar/UTC conversion based on algorithms from p. 604
+ *    of Seidelman, P. K. 1992.  Explanatory Supplement to
+ *    the Astronomical Almanac.  University Science Books,
+ *    Mill Valley. 
+ *
+ ****************************************************************************/
+
+EXTERN time_t clock_calendar2utc(int year, int month, int day);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __INCLUDE_NUTTX_TIME_H */
diff --git a/lib/Makefile b/lib/Makefile
index e00eb5c8c4..b2792cdf38 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -83,6 +83,8 @@ UNISTD_SRCS	+=  lib_chdir.c lib_getcwd.c
 endif
 endif
 
+TIME_SRCS	= lib_mktime.c lib_gmtimer.c lib_timeutils.c
+
 NET_SRCS	= lib_htons.c lib_htonl.c lib_inetntoa.c lib_etherntoa.c
 
 LIBGEN_SRCS	= lib_basename.c lib_dirname.c
@@ -98,8 +100,8 @@ DQ_SRCS		= dq_addlast.c dq_addfirst.c dq_addafter.c dq_addbefore.c \
 DBG_SRCS	= lib_dbg.c lib_dumpbuffer.c
 
 CSRCS		= $(MISC_SRCS) $(STRING_SRCS) $(CTYPE_SRCS) $(STDIO_SRCS) $(STDLIB_SRCS) \
-		  $(MATH_SRCS) $(UNISTD_SRCS) $(NET_SRCS) $(LIBGEN_SRCS) $(REGEX_SRCS) \
-		  $(SQ_SRCS) $(DQ_SRCS) $(DBG_SRCS) 
+		  $(MATH_SRCS) $(UNISTD_SRCS) $(TIME_SRCS) $(NET_SRCS) $(LIBGEN_SRCS) \
+		  $(REGEX_SRCS) $(SQ_SRCS) $(DQ_SRCS) $(DBG_SRCS) 
 COBJS		= $(CSRCS:.c=$(OBJEXT))
 
 SRCS		= $(ASRCS) $(CSRCS)
diff --git a/sched/gmtime_r.c b/lib/lib_gmtimer.c
similarity index 53%
rename from sched/gmtime_r.c
rename to lib/lib_gmtimer.c
index 98658676e1..2758acd1a7 100644
--- a/sched/gmtime_r.c
+++ b/lib/lib_gmtimer.c
@@ -1,7 +1,7 @@
-/************************************************************
- * gmtime_r.c
+/****************************************************************************
+ * lib/lib_gmtimer.c
  *
- *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -14,7 +14,7 @@
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
- * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ * 3. Neither the name NuttX nor the names of its contributors may be
  *    used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -31,56 +31,61 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Included Files
- ************************************************************/
+ ****************************************************************************/
 
+#include <nuttx/config.h>
 #include <sys/types.h>
+
 #include <time.h>
 #include <errno.h>
 #include <debug.h>
-#include "clock_internal.h"
 
-/************************************************************
+#include <nuttx/time.h>
+
+/****************************************************************************
  * Definitions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Type Declarations
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Function Prototypes
- ************************************************************/
+ ****************************************************************************/
 
 /* Calendar/UTC conversion routines */
 
 static void   clock_utc2calendar(time_t utc, int *year, int *month, int *day);
+#ifdef CONFIG_GREGORIAN_TIME
 static void   clock_utc2gregorian (time_t jdn, int *year, int *month, int *day);
 
 #ifdef CONFIG_JULIAN_TIME
 static void   clock_utc2julian(time_t jdn, int *year, int *month, int *day);
 #endif /* CONFIG_JULIAN_TIME */
+#endif /* CONFIG_GREGORIAN_TIME */
 
-/**********************************************************
+/**************************************************************************
  * Public Constant Data
- **********************************************************/
+ **************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Public Variables
- ************************************************************/
+ ****************************************************************************/
 
-/**********************************************************
+/**************************************************************************
  * Private Variables
- **********************************************************/
+ **************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Function:  clock_calendar2utc, clock_gregorian2utc,
  *            and clock_julian2utc
  *
@@ -90,8 +95,9 @@ static void   clock_utc2julian(time_t jdn, int *year, int *month, int *day);
  *    1992.  Explanatory Supplement to the Astronomical
  *    Almanac.  University Science Books, Mill Valley. 
  *
- ************************************************************/
+ ****************************************************************************/
 
+#ifdef CONFIG_GREGORIAN_TIME
 static void clock_utc2calendar(time_t utc, int *year, int *month, int *day)
 {
 #ifdef CONFIG_JULIAN_TIME
@@ -132,8 +138,8 @@ static void clock_utc2gregorian(time_t jd, int *year, int *month, int *day)
   *day   = d;
 }
 
-
 #ifdef CONFIG_JULIAN_TIME
+
 static void clock_utc2julian(time_t jd, int *year, int *month, int *day)
 {
   long	j, k, l, n, d, i, m, y;
@@ -153,26 +159,114 @@ static void clock_utc2julian(time_t jd, int *year, int *month, int *day)
   *month = m;
   *day   = d;
 }
+
 #endif /* CONFIG_JULIAN_TIME */
+#else/* CONFIG_GREGORIAN_TIME */
 
-/************************************************************
+static void clock_utc2calendar(time_t days, int *year, int *month, int *day)
+{
+  int     value;
+  int     tmp;
+  boolean leapyear;
+
+  /* There must be a better way to do this than the brute for method below */
+
+  value = 70;
+  for (;;)
+    {
+      /* Is this year a leap year (we'll need this later too) */
+
+      leapyear = clock_isleapyear(value + 1900);
+
+      /* Get the number of days in the year */
+
+      tmp = (leapyear ? 366 : 365);
+
+      /* Do we have that many days? */
+
+      if (days >= tmp)
+        {
+           /* Yes.. bump up the year */
+
+           value++;
+           days -= tmp;
+        }
+      else
+        {
+           /* Nope... then go handle months */
+
+           break;
+        }
+    }
+
+  /* At this point, value has the year and days has number days into this year */
+
+  *year = value;
+
+  /* Handle the month */
+
+  value = 0; /* zero-based */
+  for (;;)
+    {
+      /* Get the number of days that occurred before the beginning of the next month */
+
+      tmp = g_daysbeforemonth[value + 1];
+      if (value >= 2 && leapyear)
+        {
+          tmp++;
+        }
+
+      /* Does that equal or exceed the number of days we have remaining? */
+
+      if (tmp >= days)
+        {
+          /* Yes.. this is the one we want.  The 'days' for this number of days that
+           * occurred before this month.
+           */
+
+          days -= g_daysbeforemonth[value];
+          break;
+        }
+      else
+        {
+           /* No... try the next month */
+
+           value++;
+        }
+    }
+
+  /* At this point, value has the month into this year (zero based) and days has
+   * number of days into this month (zero based)
+   */
+
+  *month = value;
+  *day   = days + 1; /* 1-based */
+}
+
+#endif /* CONFIG_GREGORIAN_TIME */
+
+/****************************************************************************
  * Public Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Function:  gmtime_r
  *
  * Description:
  *  Time conversion (based on the POSIX API)
  *
- ************************************************************/
+ ****************************************************************************/
 
 struct tm *gmtime_r(const time_t *clock, struct tm *result)
 {
   time_t time;
   time_t jdn;
-  int year, month, day;
-  int hour, min, sec;
+  int    year;
+  int    month;
+  int    day;
+  int    hour;
+  int    min;
+  int    sec;
 
   /* Get the seconds since the EPOCH */
 
@@ -213,3 +307,4 @@ struct tm *gmtime_r(const time_t *clock, struct tm *result)
 
   return result;
 }
+
diff --git a/lib/lib_mktime.c b/lib/lib_mktime.c
new file mode 100644
index 0000000000..594a0672b0
--- /dev/null
+++ b/lib/lib_mktime.c
@@ -0,0 +1,149 @@
+/****************************************************************************
+ * lib/lib_mktime.c
+ *
+ *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+
+#include <time.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  mktime
+ *
+ * Description:
+ *  Time conversion (based on the POSIX API)
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_GREGORIAN_TIME
+time_t mktime(struct tm *tp)
+{
+  time_t ret;
+  time_t jdn;
+
+  /* Get the EPOCH-relative julian date from the calendar year,
+   * month, and date
+   */
+
+  jdn = clock_calendar2utc(tp->tm_year+1900, tp->tm_mon+1, tp->tm_mday);
+  sdbg("jdn=%d tm_year=%d tm_mon=%d tm_mday=%d\n",
+       (int)jdn, tp->tm_year, tp->tm_mon, tp->tm_mday);
+
+  /* Return the seconds into the julian day. */
+
+  ret = ((jdn*24 + tp->tm_hour)*60 + tp->tm_min)*60 + tp->tm_sec;
+  sdbg("ret=%d tm_hour=%d tm_min=%d tm_sec=%d\n",
+       (int)ret, tp->tm_hour, tp->tm_min, tp->tm_sec);
+
+  return ret;
+}
+#else
+
+/* Simple version that only works for dates within a (relatively) small range
+ * from the epoch.  It does not handle earlier days on longer days where leap
+ * seconds, etc. apply.
+ */
+
+time_t mktime(struct tm *tp)
+{
+  unsigned int days;
+
+  /* Years since epoch in units of days (ignoring leap years). */
+
+  days = (tp->tm_year - 70) * 365;
+
+  /* Add in the extra days for the leap years prior to the current year. */
+
+  days += (tp->tm_year - 69) >> 2;
+
+  /* Add in the days up to the beginning of this month (ignoring any possible leap day). */
+
+  days += (time_t)g_daysbeforemonth[tp->tm_mon];
+
+  /* Add in the leap day for this year (months are zero based) */
+
+  if (tp->tm_mon >= 2 && clock_isleapyear(tp->tm_year + 1900))
+    {
+      days++;
+    }
+
+  /* Add in the days since the beginning of this month (days are 1-based). */
+
+  days += tp->tm_mday - 1;
+
+  /* Then convert the seconds and add in hours, minutes, and seconds */
+
+  return ((days * 24 + tp->tm_hour) * 60 + tp->tm_min) * 60 + tp->tm_sec;
+}
+#endif /* CONFIG_GREGORIAN_TIME */
+
diff --git a/sched/mktime.c b/lib/lib_timeutils.c
similarity index 56%
rename from sched/mktime.c
rename to lib/lib_timeutils.c
index f842e2435b..31404edded 100644
--- a/sched/mktime.c
+++ b/lib/lib_timeutils.c
@@ -1,7 +1,7 @@
-/************************************************************
- * mktime.c
+/****************************************************************************
+ * lib/lib_calendar2utc.c
  *
- *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -14,7 +14,7 @@
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
- * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ * 3. Neither the name NuttX nor the names of its contributors may be
  *    used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -31,46 +31,56 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Included Files
- ************************************************************/
+ ****************************************************************************/
 
+#include <nuttx/config.h>
 #include <sys/types.h>
+
 #include <time.h>
 #include <debug.h>
-#include "clock_internal.h"
 
-/************************************************************
+#include <nuttx/time.h>
+
+/****************************************************************************
  * Definitions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Type Declarations
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Function Prototypes
- ************************************************************/
+ ****************************************************************************/
 
-/**********************************************************
+/****************************************************************************
  * Public Constant Data
- **********************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Public Variables
- ************************************************************/
+ ****************************************************************************/
 
-/**********************************************************
+#ifndef CONFIG_GREGORIAN_TIME
+uint16 g_daysbeforemonth[13] =
+{
+  0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365
+};
+#endif
+
+/****************************************************************************
  * Private Variables
- **********************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Function:  clock_gregorian2utc, clock_julian2utc
  *
  * Description:
@@ -79,8 +89,9 @@
  *    Explanatory Supplement to the Astronomical Almanac.
  *    University Science Books, Mill Valley. 
  *
- ************************************************************/
+ ****************************************************************************/
 
+#ifdef CONFIG_GREGORIAN_TIME
 static time_t clock_gregorian2utc(int year, int month, int day)
 {
   int temp;
@@ -102,43 +113,29 @@ static time_t clock_julian2utc(int year, int month, int day)
     + (275*month)/9
     + day + 1729777;
 }
-#endif
+#endif /* CONFIG_JULIAN_TIME */
+#endif /* CONFIG_GREGORIAN_TIME */
 
-/************************************************************
+/****************************************************************************
  * Public Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
- * Function:  mktime
+/****************************************************************************
+ * Function:  clock_isleapyear
  *
  * Description:
- *  Time conversion (based on the POSIX API)
+ *    Return true if the specified year is a leap year
  *
- ************************************************************/
+ ****************************************************************************/
 
-time_t mktime(struct tm *tp)
+#ifndef CONFIG_GREGORIAN_TIME
+int clock_isleapyear(int year)
 {
-  time_t ret;
-  time_t jdn;
-
-  /* Get the EPOCH-relative julian date from the calendar year,
-   * month, and date
-   */
-
-  jdn = clock_calendar2utc(tp->tm_year+1900, tp->tm_mon+1, tp->tm_mday);
-  sdbg("jdn=%d tm_year=%d tm_mon=%d tm_mday=%d\n",
-       (int)jdn, tp->tm_year, tp->tm_mon, tp->tm_mday);
-
-  /* Return the seconds into the julian day. */
-
-  ret = ((jdn*24 + tp->tm_hour)*60 + tp->tm_min)*60 + tp->tm_sec;
-  sdbg("ret=%d tm_hour=%d tm_min=%d tm_sec=%d\n",
-       (int)ret, tp->tm_hour, tp->tm_min, tp->tm_sec);
-
-  return ret;
+  return year % 400 ? (year % 100 ? (year % 4 ? 0 : 1) : 0) : 1;
 }
+#endif /* !CONFIG_GREGORIAN_TIME */
 
-/************************************************************
+/****************************************************************************
  * Function:  clock_calendar2utc
  *
  * Description:
@@ -147,8 +144,9 @@ time_t mktime(struct tm *tp)
  *    the Astronomical Almanac.  University Science Books,
  *    Mill Valley. 
  *
- ************************************************************/
+ ****************************************************************************/
 
+#ifdef CONFIG_GREGORIAN_TIME
 time_t clock_calendar2utc(int year, int month, int day)
 {
   int dyear;
@@ -209,3 +207,20 @@ time_t clock_calendar2utc(int year, int month, int day)
 
 #endif /* CONFIG_JULIAN_TIME */
 }
+#else
+time_t clock_calendar2utc(int year, int month, int day)
+{
+  struct tm t;
+
+  /* mktime can (kind of) do this */
+
+  t.tm_year = year;
+  t.tm_mon  = month;
+  t.tm_mday = day;
+  t.tm_hour = 0;
+  t.tm_min  = 0;
+  t.tm_sec  = 0;
+  return mktime(&t);
+}
+#endif /* CONFIG_GREGORIAN_TIME */
+
diff --git a/sched/Makefile b/sched/Makefile
index b16ab0b948..288aade45c 100644
--- a/sched/Makefile
+++ b/sched/Makefile
@@ -71,8 +71,8 @@ TIME_SRCS	= sched_processtimer.c
 ifneq ($(CONFIG_DISABLE_SIGNALS),y)
 TIME_SRCS	+= sleep.c usleep.c
 endif
-CLOCK_SRCS	= clock_initialize.c mktime.c gmtime_r.c clock_settime.c clock_gettime.c \
-		  clock_getres.c clock_time2ticks.c clock_abstime2ticks.c clock_ticks2time.c
+CLOCK_SRCS	= clock_initialize.c clock_settime.c clock_gettime.c clock_getres.c \
+		  clock_time2ticks.c clock_abstime2ticks.c clock_ticks2time.c
 
 SIGNAL_SRCS	= sig_initialize.c \
 		  sig_action.c sig_procmask.c sig_pending.c sig_suspend.c \
diff --git a/sched/clock_initialize.c b/sched/clock_initialize.c
index 7b63a65215..8dc8a00e83 100644
--- a/sched/clock_initialize.c
+++ b/sched/clock_initialize.c
@@ -1,7 +1,7 @@
-/************************************************************
+/****************************************************************************
  * clock_initialize.c
  *
- *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -14,7 +14,7 @@
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
- * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ * 3. Neither the name NuttX nor the names of its contributors may be
  *    used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -31,61 +31,65 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Included Files
- ************************************************************/
+ ****************************************************************************/
 
+#include <nuttx/config.h>
 #include <sys/types.h>
+
 #include <time.h>
 #include <errno.h>
 #include <debug.h>
+#include <nuttx/time.h>
+
 #include "clock_internal.h"
 
-/************************************************************
+/****************************************************************************
  * Definitions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Type Declarations
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Function Prototypes
- ************************************************************/
+ ****************************************************************************/
 
-/**********************************************************
+/**************************************************************************
  * Public Constant Data
- **********************************************************/
+ **************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Public Variables
- ************************************************************/
+ ****************************************************************************/
 
 volatile uint32 g_system_timer = 0;
-struct timespec g_basetime = {0,0};
-uint32 g_tickbias = 0;
+struct timespec g_basetime     = {0,0};
+uint32 g_tickbias               = 0;
 
-/**********************************************************
+/**************************************************************************
  * Private Variables
- **********************************************************/
+ **************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Private Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Public Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Function: clock_initialize
  *
  * Description:
  *   Perform one-time initialization of the timing facilities.
  *
- ************************************************************/
+ ****************************************************************************/
 
 void clock_initialize(void)
 {
@@ -112,7 +116,7 @@ void clock_initialize(void)
   g_tickbias = 0;
 }
 
-/************************************************************
+/****************************************************************************
  * Function: clock_timer
  *
  * Description:
@@ -120,7 +124,7 @@ void clock_initialize(void)
  *   time clock interrupt occurs.  The interval of this
  *   clock interrupt must be MSEC_PER_TICK
  *
- ************************************************************/
+ ****************************************************************************/
 
 void clock_timer(void)
 {
diff --git a/sched/clock_internal.h b/sched/clock_internal.h
index 2c298983b0..7d1dbb6293 100644
--- a/sched/clock_internal.h
+++ b/sched/clock_internal.h
@@ -1,7 +1,7 @@
 /********************************************************************************
  * clock_internal.h
  *
- *   Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -49,17 +49,6 @@
  * Definitions
  ********************************************************************************/
 
-#define JD_OF_EPOCH           2440588    /* Julian Date of noon, J1970 */
-
-#ifdef CONFIG_JULIAN_TIME
-
-# define GREG_DUTC           -141427    /* Default is October 15, 1582 */
-# define GREG_YEAR            1582
-# define GREG_MONTH           10
-# define GREG_DAY             15
-
-#endif /* CONFIG_JULIAN_TIME */
-
 /********************************************************************************
  * Public Type Definitions
  ********************************************************************************/
@@ -78,7 +67,6 @@ extern uint32          g_tickbias;
 extern void weak_function clock_initialize(void);
 extern void weak_function clock_timer(void);
 
-extern time_t clock_calendar2utc(int year, int month, int day);
 extern int    clock_abstime2ticks(clockid_t clockid,
                                   FAR const struct timespec *abstime,
                                   FAR int *ticks);